Method of inhibiting freezing and improving flow and handleability characteristics of solid, particulate materials

Abstract

A stable foam having foam bubble diameters of 0.005-0.015 inches and being comprised of from about 10-30 wt. % of a brine freeze control agent selected from the group consisting of sodium chloride, calcium chloride, magnesium chloride, potassium chloride, borax, potassium thiocyanate, potassium acetate, sodium acetate, and sodium nitrite, anionic surfactant, amphoteric surfactant, and water is applied to solid, particulate materials such as coal or mineral ores to inhibit freezing and improve handleability characteristics of the particulate materials. The foam optionally may contain additional freeze control agents such as ethylene glycol or cellulose ethers.

We claim: 
     
       1. Method of inhibiting freezing and improving flow and handleability characteristics of solid, particulate materials comprising: forming a stable foam having foam bubble diameters of 0.005-0.015 inches, said foam comprising from about 10-30 wt. % of a brine freeze control agent selected from the group consisting of sodium chloride, calcium chloride, magnesium chloride, potassium chloride, borax, potassium thiocyanate, potassium acetate, sodium acetate, and sodium nitrite, anionic surfactant, amphoteric surfactant and water, and   contacting said solid, particulate materials with said stable foam.   
     
     
       2. Method as recited in claim 1 comprising contacting said solid, particulate materials with about 0.5-5 pints of said freeze control agent per ton of said solid, particulate materials. 
     
     
       3. Method as recited in claim 1 wherein said anionic surfactant is present in an amount of from 1-5 parts by weight per part by weight of said amphoteric surfactant. 
     
     
       4. Method as recited in claim 3 wherein said anionic surfactant comprises an alkyl ether sulfate. 
     
     
       5. Method as recited in claim 3 wherein said amphoteric surfactant comprises a betaine derivative selected from the group consisting of coco betaine, coco amido betaine, alkyl betaine, coco imadozoline betaine, coco amido alkyl betaine, fatty acid amido alkyl betaine, and stearyl betaine surfactants. 
     
     
       6. Method as recited in claim 1 wherein said brine comprises calcium chloride. 
     
     
       7. Method as recited in claim 1 wherein said foam further comprises a polyhydroxyalkane or mono- or di-alkyl ether thereof as a freeze control agent. 
     
     
       8. Method as recited in claim 7 wherein said polyhydroxyalkane or mono- or di-alkyl ether thereof comprises a member selected from the group consisting of ethylene glycol, propylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, dipropylene glycol, tripropylene glycol, glycerine, sugar and mixtures thereof. 
     
     
       9. Method as recited in claim 8 wherein said polyhydroxyalkane or mono- or di-alkyl ether thereof comprises ethylene glycol. 
     
     
       10. Method as recited in claim 1 wherein said foam further comprises a cellulose ether as a freeze controlage. 
     
     
       11. A method as recited in claim 10 wherein said cellulose ether comprises a member selected from the group consisting of anionic cellulosic ethers and non-ionic cellulose ethers. 
     
     
       12. A method as recited in claim 11 wherein said cellulose ether comprises an anionic cellulosic ether. 
     
     
       13. A method as recited in claim 12 wherein said anionic cellulosic ether comprises carboxyloweralkylcellulose. 
     
     
       14. A method as recited in claim 13 wherein said carboxyloweralkylcellulose comprises carboxymethylcellulose. 
     
     
       15. A method as recited in claim 11 wherein said non-ionic cellulose ether comprises a hydroxyalkylcellulose. 
     
     
       16. Method as recited in claim 1 comprising mixing said freeze control agent, surfactant, and water with air to form said foam, wherein about 1 gallon of said freeze control agent, surfactant and water combination is mixed with about 1-100 scf of air. 
     
     
       17. Method as recited in claim 16 comprising mixing about 1 gallon of said freeze control agent, surfactant, and water combination with about 1-10 scf air. 
     
     
       18. Method as recited in claim 1 wherein said freeze control agent is present in an amount of about 10-500 parts by weight based upon weight of said surfactant. 
     
     
       19. Method as recited in claim 18 wherein said freeze control agent is present in an amount of about 25-250 parts by weight based upon weight of said surfactant.